smug
Concise Oxford English Dictionary © 2008 Oxford University Press:
smug/smʌɡ/
▶adjective (smugger, smuggest) irritatingly pleased with oneself; self-satisfied.
– derivatives
smugly adverb,
smugness noun.
smugly adverb,
smugness noun.
– origin C16 (orig. in the sense ‘neat, spruce’): from Low Ger. smuk ‘pretty’.
'smug' also found in these Oxford entries:

